Recently, thinning and miniaturization of a semiconductor device and its package have been increasingly demanded. Therefore, as the semiconductor device and its package, flip chip type semiconductor devices in which a semiconductor element such as a semiconductor chip is mounted (flip chip-connected) on a substrate by means of flip chip bonding have been widely utilized. In such flip chip connection, a semiconductor chip is fixed to a substrate in a form where a circuit face of the semiconductor chip is opposed to an electrode-formed face of the substrate. In such a semiconductor device or the like, there may be a case where the back surface of the semiconductor chip is protected with a protective film to prevent the semiconductor chip from damaging or the like (see, Patent Document 1 to 3).
Patent Document 1: JP-A-2008-166451
Patent Document 2: JP-A-2008-006386
Patent Document 3: JP-A-2007-261035
However, in order to protect a back surface of a semiconductor chip by the protective film, it is necessary to add a new step for attaching the protective film to the back surface of the semiconductor chip obtained in a dicing step. As a result, the number of steps increases and production cost and the like increase. Accordingly, for the purpose of reducing the production cost, the present inventors have developed a dicing tape-integrated film for semiconductor back surface and filed an application therefor (not yet published at the time of filing the present application). The dicing tape-integrated film for semiconductor back surface has a structure including a dicing tape having a base material and a pressure-sensitive adhesive layer on the base material, and a film for flip chip type semiconductor back surface formed on the pressure-sensitive adhesive layer of the dicing tape.
At the production of the semiconductor device, the dicing tape-integrated film for semiconductor back surface is used as follows. First, a semiconductor wafer is attached onto the film for flip chip type semiconductor back surface in the dicing tape-integrated film for semiconductor back surface. Next, the semiconductor wafer is diced to form a semiconductor element. Subsequently, the semiconductor element is peeled from the pressure-sensitive adhesive layer of the dicing tape and picked up together with the film for flip chip type semiconductor back surface and then the semiconductor element is flip chip-connected onto an adherend such as a substrate. Consequently, a flip chip type semiconductor device is obtained.
For the semiconductor wafer dicing, widely employed is a so-called full-cut process of dicing to a depth reaching the base material layer of the dicing tape over the film for semiconductor back surface as the cutting depth of the dicing blade. Heretofore, taking the matter into consideration that the thickness of the pressure-sensitive adhesive layer is 10 μm or so and taking the dicing machine accuracy into consideration, much employed is a method of evading the failure in the dicing step by dicing to the base material over the pressure-sensitive adhesive layer in full-cut operation for taking production margin. Accordingly, the subsequent picking-up process enables integrally peeling the semiconductor chip along with the film for semiconductor back surface, without requiring any additional step or operation of cutting the film for semiconductor back surface.
However, cutting to the base material produces base material-derived cutting dust, and the cutting dust adheres to the side of the diced semiconductor chips and may form a deposit of so-called burr around the chips. When the semiconductor chip with such burr is built in a semiconductor device, it may cause interconnection failure to adherends and contamination of substrate circuits, which may result in lowering the reliability of semiconductor devices.